This development is based against the Bitcoin Unlimited 'dev' branch, and has been submitted as PR458 to BU [2].The naming of the new 'bipgenvb_forks' output section in the 'getblockchain' RPC interface is to be considered temporary while the BIP has no formal number.

I would be happy to get any feedback while I implement a corresponding pull request for a reference implementation on Bitcoin Core. Due to other commitments this may come at a later stage - if someone else is eager to port it over, please feel free.